1. Field of the Invention
The present general inventive concept relates to a traveling robot, and more particularly, to a traveling robot to enhance a traveling performance by its simple structure.
2. Description of the Related Art
Generally, a robot performs dangerous, simply repetitive, precise, large-scale or a lot of work in place of a human being. The robot has been widely utilized in the areas of industry, military, home and so on according to the development of the robotics. As, in many cases, the robot moves between spaces to perform predetermined operations, a traveling device is necessary to such kind of a robot. Thus, research on a technology in the traveling device of the robot has been made, especially on a technology about the traveling device by which the robot can smoothly travel while keeping its balance without rotating when traveling on an uneven surface such as a traveling surface with steps.
FIGS. 1A to 1C are schematic views illustrating traveling states of a conventional traveling robot. As illustrated in FIGS. 1A to 1C, a traveling robot 101 has a housing 110, a rear wheel 130 and a driving part 120 to travel on a travel surface S. The housing 110 is provided with a function part (not illustrated) for performing a predetermined function. The rear wheel 130 is fixedly supported to a rear side, which is located opposite to a traveling direction d of the housing 110. The rear wheel 130 rotates idly and serves to support the housing 110 against the surface S being traveled.
The driving part 120 has a frame 122, a driving wheel 124 and a front wheel 126. The frame 122 is rotatably coupled to the housing 110 by a hinge 112. The driving wheel 124 is disposed on the right and left sides of the frame 122 respectively. The driving wheel 124 receives driving power from a driving motor 124a and allows the housing 110 to travel in the traveling direction d. The front wheel 126 is supported at a front side of the housing 110, which is located in front of the driving wheel 124 in the traveling direction d of the frame 122. The single front wheel 126 is disposed and rotates idly to support the housing 110 with respect to the travel surface S. The frame 122 is rotated on the housing 110 by the hinge 112, thus the driving wheel 124 and the front wheel 126 are integrally rotated with the frame 122. The above traveling robot 101 is disclosed in U.S. Pat. No. 5,350,033.
However, when such a robot 101 encounters an obstacle 0, such as a stepped part, on a road being traveled, its traveling performance may be deteriorated. As illustrated in FIG. 1A, when the traveling robot 101 surmounts the obstacle 0, the front wheel 126 firstly climbs up the obstacle 0. Accordingly, the frame 122 is rotated about the hinge 112 in a direction for the housing 112 to maintain its balance.
As illustrated in FIG. 1B, when the traveling robot 101 further travels in the direction d, the driving wheel 124 climbs up the obstacle 0, so that the center of gravity of the traveling robot 101 shifts backward and is concentrated upon the rear wheel 130. In this case, the driving wheel 124 may not receive a traction force enough for the driving, which makes the rotating driving wheel 124 slip on the obstacle 0. As a result, the traveling robot 101 cannot surmount the obstacle 0 easily.
Referring to FIG. 1C, when the traveling robot 101 further travels in the traveling direction d, the driving wheel 24 surmounts the obstacle 0 and the rear wheel 130 is positioned on the obstacle 0, so that the center of gravity of the traveling robot 101 rapidly shifts to the front side of the robot 101. In this case, the front wheel 126 abruptly contacts the traveling surface S, whereby the housing 112 may begin to sway.
Furthermore, the deterioration concerning the traveling performance of the traveling robot 101 as described above may become even worse when the height of the obstacles 0 to be surmounted by right and left driving wheel 124 are different from each other. That is, since the single front wheel 126 and a pair of driving wheels 124 are supported by and integrally linked with the frame 122, the traveling robot 101 may not be adapted to the height difference between the obstacles 0 to be surmounted by the right and left driving wheels 124, and thus the slipping of the driving wheel 124 and the swaying of the housing 110 may be intensified.